Swivel connection for vehicle units



Jan. 26, 1954 R. G. HoLLn-IELD SWIVEL CONNECTION FOR VEHICLE UNIT 5 Sheets-Sheet l Filed Jan. 2l, 1950 Jan. 26, 1954 R. G. HOLLIFIELD SWIVEL CONNECTION FOR VEHICLE UNITS INVENTOR. y 63, /aL/Fnm KM' d? 5 Sheets-Sheet 2 Jn- 26 1954 R. G. HoLLlFnELD 2,667,365

SWIVEL CONNECTION FOR VEHICLE UNITS Filed Jan. 2l, 1950 5 Sheets-Sheet 5 76 /f' 7 @06 9/ Mmmgymw/ 4 j l v l i Maggi/i121# MZ m, V292 INVENTOR. 7 f6!! G. H0LL/F7Ep @j/@dw Jan. 26, 1954 R. G. HoLLlFlELD 2,667,365

SWIVEL CONNECTION FOR VEHICLE UNITS Filed Jan. 2l, 1950 5 Sheets-Sheet 4 A. f. '.l.....'

l I. I 3a u MVL --32 f' f' 25' 2z' 7 35 5707/ l l 4g INVENTOR.

6 @Y 6. /laLL/F/E l Kamm 6 I f/rroeA//(S Jan. 26, 1954 R. G. HOLLIFIELD swIvEL CONNECTION FOR VEHICLE UNITS 5 Sheets-Slieet 5 Filed Jan. 2l, 1950 JNVENTOR. )Voy 6.4 /aLL/F'IELQ Patented Jan. 26, 1954 UNITED STATES PATENT OFFICE 2,667,365 SWIVEL CONNECTION FOR VEHICLE UNITS Roy G. Hollifield, Brooklyn, N. Y. Application January 21, 1956, Serial No. 139,799

This invention relates to swivel connections for coupling vehicle units together and the invention has particular reference to a swivel connection of said character which is constructed and arranged for coupling the service lines of the units together.

An object of the invention is to provide a swivel connection for vehicle units consisting of parts adapted to slidably engage for swivelly connecting the units together and which parts have interiitting service line connections adapted to automatically engage to connect the service lines of the vehicle units together when the Vehicle units 'are moved into swivel engagement.

Another object of the invention is to provide a swivel connection for coupling vehicle units such as a tractor and semi-trailer together tovpermit of articulation of vthe tractor with reference to the semi-trailer and by which service lines such as air, oil and electric cables leading from in strumentalities on the tractor with corresponding lines connected with instrumentalities on the semi-trailer are automatically connected with the tractor and semi-trailer are connected.

Still another object of the invention is to provide means for locking the parts of the swivel connection in coupled relation.

With the foregoing and other` objects in view, reference is now made to the following specification and accompanying drawings in which the preferred embodiments of the invention are illustrated.

In the drawings:

Fig. 1 is a top plan view of a swivel connection for vehicle units constructed in accordance with the invention.

Fig. 2 is an under side view thereof.

v Fig. 3 is a top plan view of the intermediatel section of the connection.

Fig.v 4 is a vertical sectional View taken approximately on line 4-4 of Fig. 1.

Fig. 5 is a View in side elevation of the connection.

Fig. 6 is a fragmentary enlarged top plan view of the intermediate section showing the means for connecting the service lines.

Fig. 7 is an enlarged longitudinal sectional-view taken approximately on line 1 1 of Fig. 6

swivel through one of the check valves of the air service.

lines which connects the service lines of the tractor and trailer together.

Fig. 8 is a similar View taken approximately on line 8-8 of `6' through one of the check valves of the oil service lines which connects the service lines of the tractor and trailer together.

1 Claim. (Cl. 280-434) s) Fig. 9 is an enlarged longitudinal view taken approximately on line 9-9 of Fig. 6 showing the sliding connector ofthe electrical service'line Which connects the electrical cables of the tractor and trailer together.

f Fig. 10 is a cross-sectional view taken mately on line |U`I0 of Fig. 9.

Fig. 11 is an enlarged fragmentary sectional view taken approximately on line l I-.ll of Fig. 1. Fig. 12 is av similar view taken approximately onlinel2-l2 ofFig. 1. Fig. 13 .is a fragmentary bottom plan view of amo'died form of swivel connection forvehicleunits constructed in accordance with the inven' tion- Fig. 14 is an enlarged vertical sectional View taken approximately on line'l4--I4 of Fig.. -13. Fig. 15 is en enlarged fragmentary' sectional View taken approximately on line |5|5 ofFig.' 14. n Y Fig, 16 -is'a top plan View of the intermediate section ofthe clutch member shown in elevation' inFig. 14. Referring tothev drawings by characters ofv reference and more particularly to the form of, the invention illustrated in Figs. 1 to 12v thereof inclusive, the 'swivel connection is illustrated in' approxi-Y its application 'toa construction for swivelly cou-'5 The swivel connection consists of a fthwheell construction which includes a base" I0, an upper section ll and an intermediate section I2. The

base Il) is rockably mounted on the frame of the tractor and forms a support on the tractor for the forward end of the trailer. The upper section. I! is rigidly'aixed to the .trailer land4 slidably engages the intermediate section l2 for connecting the tractor and 'trailer together while the.

intermediate section' has bearing engagement with the base l0 and has a king-pin I3' affixed thereto which extends through an axial opening I4 in the top wall I5 of the base so as to swivelly connect the tractor and trailer together.

The top Wall I5 of the baseis of circular forma-- tion in plan and'hasr a' plane upper face which forms a bearing surface for the intermediate section l2. Depending from the top wall are arcuate side walls I 3 'having horizontal apertures I 9 through which extend bolts 2li which rockably connect the base upon the side frames 2l of thev plate 22 having forwardly directed tongues 23 which taper inwardly toward their forward ends and are provided with upstanding flanges 24 extending along their outer side edges. The plate 22 is secured to the under side of a flanged plate 25 aflixed to the frame of the trailer adjacent the forward end thereof to dispose the tongues 23 in forwardly projecting relation and with the opposite side edge portions 2T of the plate 22 Vprojecting outwardly beyond the! a-nges 28 of theiupperplate 25 The intermediate section I2 includes upper and lower plates 29 and 30 having flanges 3| alici: 32 respectively which interflfaarer secured.

together by longitudinally spaced boltsV 33 to dispose the plates in superposed spaced/'spartV rc1 lation. The lower plate 33 hasfvthekingep-in. #3f affixed thereto which extends through the axial opening I4 in the top wall I5 of ther base IIl` and'is secured in position therein by a two-part clamping-ring- Itddisposed' ingsnrroundin'g, relation the king-p-irnbelowf an.` annularr spacer member.:tl-if. 'Ehering member Mislfoianedrwitlt aniv annular" rib-f. 3&- wh'i-ch: sriu glyf lits 1 arr.y annular recess 3'1 in the pin for securing;the@pittpo'-Y sitiorr in: the Vbearing openingfrand connectingtthe intermediate section? t2: andbase I0? fori-'elasti-vefswivelf turningY movementabout the kingpirris ttf-vertical f Thefupperplate'ZS formedfwith a. rear. porn tion 39 which extends downwardly. and rear-- ward'lyin angular. relation and: forwardly'of-said rear portion. thef'said plate'V istV provided-iv With grooves.: Al along theY opposite'. longitudinal. side edges thereof which are formed by the inwaifdlyi directed:4 wall.. portions' 411 disposedv ini overlying spaced relation withthef upperA faces thereof: The-said, grooves are adaptedto slidably receive the. opposite-edge portions; ZT. of; the upper sec-'- tion I I for releasably connecting the intermediate andi' upper sections together; and. whichv also rreleasaoly `connects the tractor anni trailertogetner.

In connecting the tractor and trailer i'`c)gether;y

the tractor:` :tsv backed; under theforwardV portion of thetrailerintov engagementwitn the: tongues: zefortheupper section Hi whiiclislide over the inclined: portion 3.91 of" theupperfplatei 23' of the: intermediatesection I12r and@ over: the. upper plate 2a into proj ecting'v relationv therewith to: dispose the side?. edgey portionsA 2T off saldi section the'f grooves;L 405.1. Stop?v lugs:V 422 areL providedfl on the forward end of theff'uppei plate29 of`the?"inter*-J n'ietd'atesectiotr which. engagez over theY forward edge or the plate- 221V oftrie: topI section at the limiting the forward movement: ofthe upper sec-- tion H?. withf reference to the intermediate-sectionIZ;v Y

rrr order: to` automatically rooie-the tractor anti? trailer together' when; the, upper' section.: tlf errgages? tl' Stplugs 421 of the4v intermediafre` sec--V tion I2- a rock; shaft 45".' provided is mounted: for" rockinginovement.y irrv bearings 41 affixed-z to the upper facel of theilowerpl-ate: 30' and with.v the: rock. shaft extending laterally be-l tween the upper vand: lowerplates 29fand130 of the-intermediate section #21. rEhe rockshaft'd isprovided with a downwardly directed. handle 42. anapluralityr of forwardlyl extending lever arms" 56 which engagein openings in. vertically' disposed locking. studs. 5I slide-bly' arranged: in aligned-openings 52 and-53 inthe upper and-lower plates: 29. and 39 respectively. The rock.' shaft is tensioned by a coiled spring 54 for normally, rocking the shaft to dispose thestudsS-I. ingupv one: or tiret-lever arms.

wardly projected relation with the upper ends thereof protruding through the upper place 29 at the rear of the upper section II and adapted to engage thereagainst for preventing disengagement of the upper and intermediate sections II and I2.

When the tractor and trailer are to be coupled together the rock shaft ismaintained with the locking studs disposed in lowered position by means cfa slid'efy bar 5@ mountediingnides 51 att'achedto the under side of the upper plate 29. The slide bar is provided with a depending rear terminal 58 adapted to impinge against ai lever arm 5%" projecting forwardly from the rock shaft 6 for holding the rock shaft against upwardlturning movement. A spring 60 is affixedetothe slide bar 56 and to a lug 6I carried by the upper plate 29 for tensioning said slide barinto engagement with the lever arm 59.

A hand lever 62 is pivoted in an opening 63 iirtheflovfen'pi'ate 3d and is-providediwfitlr ahead off the'upper errdthereofl. 'lfheshandzileven t'erlsioi'leiiY by a spring. Sfr for norirratlly-Y dise posing. the` head?t 614-in1 underlying; relation; with: 584 for. maintainingrtha' said arm in forwardly inclined relation.a'ncfrtlelrv loollring: studsY 5tk inv upwardly. projected; positron: at? thel rear of: the; upperrk sectiorr. tit-l. Bti; manually'swinging the hand lever 62 -rtarwarchl ly against; the tension ofthe springig. therhead El! thereotis swungiorwardly fromzberreatntha lever 5t son. that; the handleiM may'th'enzba maniutlly'v swungV rearwaidlyl4 so: as1 tra rotate the rock shaft 4a antl-lowerftne-leverrarnnswlfereby tl'lesl'ide bar 'ew'ill be nrovedlty itspng to dispose the" terminal. endl thereof; im overly# ing'. relation. witrr tnezzlever arin- 519i tot the; looking: studs 51; in.. lowered` position... 'Ehe slide bari 5B. is formed wittrarrupwardlw prolj-eetingforward ende lowncli protrudeszthrougrr asl'ot. irixonef-of the: stop'lugsflt'.:V Thaforwardf. end 6B engaged byf tlieforwardedgel ofi the:- upper section II' wher-r sardi f section: elggsfthef intermediateseotibn lfzl'soastoJconnectftneatrac-f torf and trai-lei' together'toatliereby movetheislide bar forwardly tol release. the rooktl straft;v` permits the spring GIP to. rotateithe ro'cirlsfiaftso asj to move the locking studs' 5ft? into:l upwardly proj'ect'edrelation at the rear ofthe upperseo tion Hi'.

Inf tractor-trailer vehcfes-fservice lines such* as air, oil and electric are required for the? ope eration of the brakes, pump andi ligltts'tonzthe trai-lei'.`V The' air1 lines-on: thetractor include. dex- -blecondiits.l T0* and' 'l I.: which; arev connected by swing joints 69 with piping securedzin'vopenings'- 'I2 and 'I3 extendingufupwardly'tlirougrftle kingpin; t3; Above:the-king-piirnexible: conduits 14 and I5 are secured in theaupperendsof' saicti openingsv respectivelyr and corina-.ctiy with check valves 'I5 carriediby andi' projecting` forvrardly through.. a cross-head;- ti resilientlyf connected with a cross-head i9 supported by a braicl'et" secured in opstanding relation on theY forward end;L of the lower plate- 30 ofs tire` internoodiate section I2.

They ol linef on the; tractor includese exible conduits SI amd'82wliich arefconnectedby swing-1 joints'.` 88 Wi-th piping. secured. the lower' endsl of openings -f and B4- extending. upwardly-l through the king-pin I3. Above: tlre king-pinVA flexible condi-lits:t5.` andV Mi yare'secu-red in said openings `lrespectivelyI and;v connect". witnstil me@ talrlia tubesz lll..V rigidly carried: by 'andv projecting, rearwardlythrough.- said cross-head. l8r. The in ner ends of the tubes 81 slidably engag'ein check valves 89 carried by a cross-head 9| axed to a bracket 92 mounted on the upper face of the elongated plate 22 of the upper section The electrical line includes an electric cable 93 which extends through an opening 94 in the king-pin with the upper endof the cable connected with one end of a sliding connector 95. One section S9 ofV said connector is secured in an opening in the cross-head '|8 and projects forwardly therefrom and the other section 91 thereof is secured in and projects rearwardly of the cross-head 9|.

The check valve 'I6 for each of the air service lines is illustrated in detail in Fig. 7 of the drawings while the check valve 89 for each of the oil service lines is illustrated in Fig. 8 of the drawings. The check valves 'I6 each include a cylin. drical casing 99 threadedly secured in the crosshead '|8 and having apertured nuts |00 and |0| threadedly secured in the opposite ends thereof. The flexible conduits '|4 and.'|5 of the air's'ervice lines are secured in the apertured nuts of the check valves '|6 respectively and freelyengaging through the nuts |0| of the check valves respectively are stiff tubes |02 which are rigidly carried by the cross-heads 9| with the protruding ends of the tubes respectively connected with conduits |04 and |05 of the air service lines on the trailer. Aconical shaped resilient rubber sleeve |06 is arranged within` each of the check valves 'I6 against the inner face of the nut |0| in surrounding relation with the inner end of the stii tube |02 which snugly and slidably fits the same" A metallic cap 0l is fitted over the reduced end of the resilent sleeve |08 and is provided with a flange |08 extending peripherally about the en'- larged end thereof to form a seat for a coil spring |09 interposed between said ange and the inner face of the nut |00. The spring |09 together with the fluid pressure. within the valve function to resiliently retain the resilient sleeve |06 against the inner face of the nut 0|.

, In order to close off the flow of air from each of the check valves 16, a valve element ||0 is provided which includes a reduced inner end I disposed in axial alignment with the stiff tubes |02 of the valves respectively'and which is nor-v mally tensioned thereagainst by a coil spring I |2 interposed between the recessed inner end of the nut |09 and an annular flange ||3 .extending peripherally about the valve element intermediate the ends thereof. The stili tube |02 of each of the valves is formed with a plurality of apertures H through which the air ilows .when the valve is maintained in open-relation.l by the shoulder formed by the reduced end engaging against the end of the stiff tube with the-reduced inner end protruding into the open end` thereof as illustrated in Fig. 7 of the drawings' which is the position of the valve element when the tractor-trailer are in coupled relation. However, when the stiff tubes |02 are withdrawn from the resilient sleeves |06 of the check valves respectively by disconnecting the tractor and trailer, the springs ||2 function to force the annular portion of the valve elementm snugly into the inner end of the resilient sleeve |06 to thereby close off the ilow of air from the tractor. y The check valves 89 for each of the oil service lines are similar in construction to the check valves 'I6 but inconnection with the "oil servicel lines, the cylindrical casing of each of the check valves 89 isthreadedly secured in the cross-head 9| of thetrailer with ther valve rel-- valves 89 respectively and a coil spring |24 ls.`

interposed between the recessed inner end of the nut |23 and a ilange |25 of a valve element |26 so as to tension the same against the end of the stiii tubes 81 of the check valves respectively when the tractor and trailer are in coupled relation as indicated in Fig. 8 of the drawings. This disposes the valve element 26 in open relation so that the oil flows through the apertures |21:

in the stiiT tubes 81 when the'tractor and trailer are in coupled relation and when the sameare uncoupled the stii tubes 81 are withdrawn whereby the springs |24 move the valve element |26 to dispose the cylindrical portion |28 in closing relation within the resilient sleeve |20 so as toclose off the ow of the oil through the check valves.v 'Ihe electrical cable 93 is composed of a plu-- rality of conductor wires |30, ve being shown in the embodiment illustrated in -li'ig. 10 of theA drawings. The conductor wires |30 are each electrically connected with one end of a stifftube |3| extending longitudinally of the connector section 96 while the electrical cable |32 on the tractor similarly includes a corresponding number of conductor wires |33 each of which is elec trically connected with the outer end of a stiff tube |34 extending longitudinally ofthe conhector; section 91. The tubes |34 protrdudebe-l yond the inner end of the connector section 91 and are adapted to snugly t within the stiivtubes |3| for coupling the connector sections 96 and 91 together and electrically connecting the conductor wires |30 on the tractor with the conductor wires |33 on the trailer.

'I'he cross-head |9 is connected with the crosshead 'I8 in parallel spaced relation by means of bolts v|39 which slidably engage through openings in the cross-head 'I9 are are provided with coiled expansion springs |40 disposed in surrounding relation therewith and interposed between the cross-heads 'I8 and 19 so as to maintain the crosshead 18 in resiliently'spaced relation from the cross-head '|9. The cross-head 18 is provided with rearwardly projecting tapered pins |4| which are disposed in alignment with flared openings |42 in the cross-head 9| when .the tractor and trailer are being coupled together. The pins' 4| engage said openings in order to align the cross-heads l'i8 and 9| so that the stiiT tubes 811 and |02 engage in the check "valves 16 and 89 respectively, and the connector sections 96 andV 9'| engage for electrically connectingthe sections together.

The intermediate section l2 is formed with inner and outer peripheral walls |43 and |44 secured to the upper face of the bottom wall 30 and with al cover |36 secured in closing relation lon the upper edges thereof so as to provide acornpartment |3 adapted to receive oil-soaked paci@4 ing for lubricating the upper surface of the base:

l0 by seepage of the oil through the openings |38 in the bottom wall 30.'

In the form' o f the invertirn""illustrated inj 15` inclusive, a swivel connection s- Zi shownwhichfissnnilartn constructeiionswtvelly connectingfvehiclenmtstogethen sncnasa trac-- ton and senx-.traileryas .im the@ previenen form.; of. thea-invention; swivel connection.= similarly consists,l otra iitthr Wheel construction Whiclineinden abase: 14155",.an:upper;sectionV 14.5 and an intetmediater sectiona L41 which are.: similarV in; constructonvto the 'base-f ML; upper section. 1-1- and intermediate section 12.i ofthe; peviousgform. 0fv the: invention; out in this form. however, the: said sections. are-.nroi/ided with means. forv mechan-` icallyftransmitting povteirfrmrrthe;power;takeeoff` the t1:ansmissicanaotithegticactorv in additionto: service:Y lines such: as air and electric iol. the op-M erat'ronmf., the .brakes and; lighfts'ron' the trailer.

Thehasel #52. ismoimted toirocking movementomthejrame of. the tractoz` 'and 1to1-msi a. support oni-the tractonior thesforwamdndon the; traiflcn; snnilan toi the: base: 1l! the previous iorrnottlieinvention; While-.the upper section.'A mi'. isv rigidly affixed totthentrailen andislidablyvengages thefinrtennediam-:fselution` Hmfon'connectingthe tractor anda` tnai-leif together; "il'lziel intermediateA` section has bearingeneagementwitn the base 1145: and; haezazletng-pin Hi8 alxe'eethereto. which extends. through anaxal. openingzinthe top wall? 1'49'oi thefbaseiforswivellyconnecting the tractor and` trailentogether'similar to the construction in the previous;iorm'oi:V the invention.. In this form' however,-.therkingpinp i431: is; centrally aperturedy for. receivingaz sleeve trilt-whichisv welded to and dependszfronn: thexuppei: eno thereof and engages. atl its1 lower' ends! in a: centrally agenturen crossl member'. 15.1.2 is; secured at; its ends to the lower endofthefperipheral rirn1t52 of. the king pin..

lY/.EonntedlWithin' the Sleevef. 15.9 isra.r cylindrical tube 153;'Whicl1 isconnected at: its lower end to. ahousi-ngt i541 Withi-nwhichis mounteda shaft: 1155 journale for; rotatonim bearings 1:56 and 51? with' the shaft?V protruding frontthe; hoi-ising and l operatively connected. at its oil-ter4 end with. the, power take-oni of theY transmission of: the

tractor. 'Ene-shaft. E55 isprovided vvitlstv a worm` portion 158 intermediates the beacirrgsl t56j andi L51y whichwormfportion. is. engaged by a` worm gearV 159 aflxedf tothe lower endof a.. verticali shaft 161).y 'Ehesaid shaft;16111isjournaledfor. rotation .in a` bearing 1.6 I the lower; portion of= theehousi-ngA 154 and-inbearings 1.162. and 153. in; ther upper. andlowen ends ot the# cylindrical. tube:

15.3. with the shaft protruding upward-ly, through. the,king-pin.14& and-Welded .or otherwiseI aixed atitsuppcr end tothe lowersection 164e. 0L aclutch.A member 1.65. Thecylindrical. tube 153Y and housing. leltogether with the shafts l 155 and 16.0. have, vertcaL reciprocatory movement as aZ unit. with thetuloeA 153 slidably guided in the sleeve .l 5,0.

Inorder to. effect movementin opposite. direce tions, of saidunit, an. eccentric 16B ismountedon a;crossfshaftl6.`1 with theeccentrc disposed. in engagement. with a slotted extensionl formed on the underside of the housing 154. The shaft:

ll-,is mountedior turning movement ina bushing`l 11|! carriedloyvv a bracket 11'1-1 affixed to and.-

depending from the underside of the base 10. The opposite end of. the shaft protrudes through,y aV bushing 1'12 mounted. in-the side Wall 113 of the base and isprovided-with aV handle 1'14'for manually. turning theshaft torotate the eccentric for raising or loweringthe said unit.V The said eccentric is formed with an aiflnular.y groove.v 115 in .ajsideiacethereot which;y is engaged by' apin L'Ioax'riedvby said extensionv Hi8:` and extending;

.ahracket 1.282 afxedpto... the upper'. section.l 1.1i of.A

the fth Wheel construction with theshaftf. 1'80. projecting'upwardlntherethrouehi tor' operatively connecting the. same. with an. instammentalitnv carried by the-tranen sochsaseapump G11-Winch for turning these-me.. Locatedrbetween the-upper. and lower; sections.. H9? and. 16A. ci. thef clutehi member v1sitisan.in'oenirlediateclutcl'r section .1.8131

groove. 18.4?. in the` ungen face'.thereof` andwitli diametrically v extending-x groove; m5;VV inthe lower face thereof:v which, arranged ati. right:- angles with reference to: the groove 184. The" UDINE section 1x19 cf..isaid;.c1utch memberis;formentwith a. depending :rio 1.81554 adapted tosnugly fit in groove; 1:84. in the upper. face of; the.:v intermediate section m3.: .whilejzthe lowersection'. E641. iszformed; with, an.. upwanzllyv extendnig.. rib-1 tali adapted; toL snugly t in the groove 185 in the lowen'faoerzoi' the, intermediate clutcnsectiorn 1&3.; Theishaztts i and; 181i are.` thecebxc connected together through the clutch` member 155:;- wherebn thefsliatt; tlis will. be rotated by.y t'heatnmingr offfthe shaft.V lwloenthe'unit is disposed; imite-utanet most position, WherrtheY cross-.shaftV tt.y rotated toY lowerthetsaidinnit; the interimodiateY clutch. section 1 8.3: will; be: disconnected y from, the: upper section'v H9 soz as todisconncet. thefsliaitsi Huand 1180..

The; king-pin- Mlgisprovded With'tWowopene. ings.I E89 and t9@ located at.l onefside ofthe-sleeve I-fand. a-.single opening, 9511. on the.opposite side thereof. Pipelines; 1.92 and:A 193-v extendtlLn-oug-h:v the. openings; tBQCand.: 1 9115. fonconnection'withfthe air lineszonthe tractor', similar. to theairpipe lines in the previousy forme ofi' the inventi'or-r.` extending through-the: opening '1902 in thekingpin is. an electric.y calcle: t911 similan toV the electi'in GalileiY 9:3 in` the previous' form. of-tne' invention; The pipelines: 192 and 193connect-V wth. check valves. tnotshown). similar to the checlivalvesl'f in the-previous form; of? the-inverte tion for supplying ainto:k the trailer; Whilethel electric.v cable. 1%` is connected',` to a slidingconneetm:v similar to the sliding connector 95' inl the.- previous: form' of the; invention for providing' electrifcffpower lines fork the trailer;

In this `form. of the-invention. the interm-odiata` section 141 is formed with inner" andL outer peripheral wallsz19'1 and 198 :secured to ther-uppers face ofthe bottomwall. 1 99 anciwith a coverA 21101' secured in closing,l relation on the: upperedges' thereof. so as to. provide acompartment 21H` adapted' vfor. receivingoil-soaked packing forf lubricating the upperssurface ofY thebase M5flby= seepage,y of the; oil through. the openings 2&2 in` the'bottom wall 1.99@

What isI clainareriis:

In. aswivel connection. for a tractor-trailerconfit-ination,l an. apertul'od. base affixed to the tractor, upperfsectionafxed to thetrailer; an. intermedatesection @nuancering-engagement with the., base; andi., having: a..king-pirr depending" therefrom'. and.. mountedf. in the aperture iny tlfieY and trailer together, a rock shaft carried by 5 said intermediate section and having locking studs, means tensioning said rock shaft for rocking the same to move the locking studs into engagement with said upper section for locking the tractor and trailer in coupled relation, a slide bar carried by said intermediate section and operatively engaging said rock shaft to maintain the locking studs in retracted relation out of engagement with said upper section, and said slide bar having a forward end adapted to be engaged by the upper section when the tractor and trailer are coupled together for moving the slide bar to release the rock shaft to permit of movement by said tensioning means to thereby move the locking studs into engagement with the upper section.

ROY G. HOLLIFIEID.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,261,261 Menhall et al. Apr. 2, 1918 1,973,610 Connors Sept. 11, 1934 2,062,806- Casler Dec. 1, 1936 2,092,113 Fuhrman Sept. 7, 1937 2,092,115 Gurton et al Sept. 7, 1937 2,119,460 Gurton et al Mat7 31, 1938 2,178,841 Lubbers Nov. 7, 1939 2,480,413 Kirksey Aug. 30, 1949 2,485,878 Hanlon Oct. 25, 1949 

